What’s Different About Potatoes & Corn?

In Lesson 4, we give white potatoes and corn a special mention: While we encourage you to eat 1 to 3 cups of most veggies at every meal, we recommend enjoying these two vegetables in smaller quantities  — ½ cup per serving.

Is that because they’re unhealthy? No, not at all… at least, not in their whole-food form. In other words, when they haven’t been peeled, mashed, ground, powdered, creamed, French fried, and/or loaded with butter, cheese, cream, or mayo.

Like all vegetables, white potatoes and corn are a great sources of essential nutrients. White potatoes are rich in vitamin C and potassium, as well as vitamin B6. Corn boasts vitamin C, magnesium, B-vitamins, and potassium.

But even though corn and white potatoes grow like veggies and are full of nutrients, their carbohydrate content is more similar to rice or pasta.  

Check out how the two compare to broccoli in terms of carbs and calories:


Calories in 1 cup Carbs in 1 cup
Broccoli 55 11g
Corn 111 31g
White Potatoes 143 31g


White potatoes and corn stand out because they contain more starch — a form of carbohydrate that gives them their signature squishy, comforting texture. You’d probably have to force yourself to eat 2 cups of broccoli, but 2 cups of corn or potatoes can slide right down.

Making an effort to keep white potatoes and corn to ½ cup serving will prevent you from going overboard, and can help you lose weight.

As you probably know, corn and white potatoes aren’t the only starchy vegetables. They just happen to be the most popular — white potatoes are the #1 most frequently eaten vegetable in the U.S.

Peas, butternut squash, sweet potatoes, yams, and pumpkin also fall into the starchy vegetable category. All are nutrient powerhouses but are considerably higher in carbs than green leafy veggies. When you eat any of these starchy vegetables, aim for the same ½ cup serving.


Eyeball a Serving Size

a cupped hand

One ½ cup serving of corn or potatoes is about as much as you could fit in a small/cupped handful.




American Diabetes Association. Evidence-Based Nutrition Principles and Recommendations for the Treatment and Prevention of Diabetes and Related Complications. Diabetes Care. 2003 Jan;26 Suppl 1:S51-61. Doi: 10.2337/diacare.26.2007.S51

Min Li, Yingli Fan, Xiaowei Zhang,Wenshang Hou, Zhenyu Tang. Fruit and Vegetable Intake and Risk of Type 2 Diabetes Mellitus: Meta-Analysis of Prospective Cohort Studies. BMJ Open. 2014 Nov 5;4(11):e005497. doi: 10.1136/bmjopen-2014-005497

Academy of Nutrition & Dietetics. Should People with Diabetes Eat Potatoes? https://foodandnutrition.org/blogs/stone-soup/people-diabetes-eat-potatoes/. Published April 9, 2013. Accessed June 15, 2018.

USDA. Charting the Essentials, 2017. https://www.ers.usda.gov/webdocs/publications/83344/ap-075.pdf?v=42853. Published April 2017. Accessed June 15, 2018.